17.4.1.12 Replication and Floating-Point Values

With statement-based replication, values are converted from
decimal to binary. Because conversions between decimal and
binary representations of them may be approximate, comparisons
involving floating-point values are inexact. This is true for
operations that use floating-point values explicitly, or that
use values that are converted to floating-point implicitly.
Comparisons of floating-point values might yield different
results on master and slave servers due to differences in
computer architecture, the compiler used to build MySQL, and so
forth. See Section 12.2, “Type Conversion in Expression Evaluation”, and
Section B.5.5.8, “Problems with Floating-Point Values”.